As part of Salix’s two day Wetlands Conference (7-8 July 2015), Cleanleach partners Salix and Naturalea led a Cleanleach workshop on 7 July 2015 at Salix’s Croxton Park Nursery, near Thetford in Norfolk.

Around 60 people - including landscape architects, ecologists, academics, consultants and engineers from wetland and river-related businesses - attended the Cleanleach project presentation and demonstration.

See the full presentation:

The first presentation was given by Albert Sorolla of Naturalea, who outlined the environmental problems arising from nutrient pollution from intensive agriculture and horticulture.

Albert went on to explain the objective and features of the Cleanleach technological solution, the demonstration project which Naturalea has set up on Spain and the potential applications for the new system.

David Holland, Technical Director for Salix, then described the Cleanleach demonstration project which Salix has set up at Croxton Park and how it differs from the Naturalea one.

He explained that rainwater is collected from the nursery’s polytunnels and then stored in tanks. This water is cleaned by the Cleanleach system and then recycled back into tanks to then irrigate pot grown plants.

The main differences with the Salix demonstration project are that the water is filtered through sand mixed with Xylit fibres to provide structure and the project has a floating wetland ‘BioHaven’ element. The plant species used include Phragmites australis, Carex acutiformis, Iris pseudacorus and Lythrum salicaria.

He described different potential waste water treatment applications for the system.

Albert then outlined the latest phase of research where they are studying how different plants species perform in the system at the Urban River Lab outdoor experimental laboratory. Here 18 channels of 12m in length are planted with different plant species and 12 constructed wetlands divided between four steel tanks, where the circulating water is obtained from the effluent of the waste water treatment plant.

Delegates were then taken to see the Salix Cleanleach demonstration project for themselves, where David Holland explained the components of the system and how it works, including the use of a by-product of local whisky production instead of the Spanish beer used by Naturalea, to provide to promote the nitrate removal.

The presentations and demonstration led to a number of questions from attendees and discussion about potential applications for the system.